Rail inspection device

Abstract

The track inspection device 1 includes a trolley 10 that travels along a pair of travel tracks 80 and guide tracks 83 in the travel direction X. The track inspection device 1 further includes a determination unit that performs contact period determination processing, curve entry period determination processing, and track inspection processing. The contact period determination processing determines the period when the guide wheel 40 contacts the guide track 83, i.e., the contact period. The curve entry period determination processing determines the period when the right front wheel 24 and the left front wheel 23 enter the curve section 72 from the straight section 71, i.e., the curve entry period. The track inspection processing determines whether the position of the guide track 83 is within an appropriate range based on the relationship between the curve entry period and the contact period.

Description

Technical Field

[0001] The present invention relates to a track inspection device, the track inspection device comprising a trolley that travels along a pair of travel tracks and a guide track in a travel direction. Prior Technology

[0002] An example of the track inspection device described above has been disclosed in Japanese Patent Application Publication No. 2018-62241 (Patent Document 1). In the following description of the prior art, the symbols shown in parentheses are those of Patent Document 1. As shown in Figure 5 of Patent Document 1, the track inspection device (2) of Patent Document 1 includes a trolley (20) that travels along a pair of travel tracks (91) and a guide rail (92). The guide rail (92) is positioned above the travel tracks (91) at the center of the width direction (W) of the pair of travel tracks (91). The trolley (20) includes wheels (22) that roll on the travel tracks (91), a first roller (31) that rolls in contact with the side (91a) of the travel tracks (91), and a second roller (32) that rolls in contact with the side (92a) of the guide rail (92).

[0003] As described in paragraph 0003 of Patent Document 1, it is important to ensure that the positional relationship between the guide rail and the travel track is appropriate. In this regard, in the track inspection device (2) shown in Figure 5 of Patent Document 1, the trolley (20) is equipped with a first position sensor (41) and a second position sensor (42), and the width-direction interval (Δw) between the side (91a) of the travel track (91) and the side (92a) of the guide rail (92) is calculated based on the detection results of these two sensors. Furthermore, based on the calculated width-direction interval (Δw), it is determined whether there is any abnormality in the arrangement of the travel track (91) and the guide rail (92). Summary of the Invention

[0004] However, the behavior of the trolley when the guide rail (guide rail in Patent Document 1) is not within an appropriate range usually differs from the behavior of the trolley when the guide rail is within an appropriate range. Therefore, it is conceivable that, instead of using two dedicated sensors on the trolley to calculate the width distance between the traveling track and the guide rail, as in the track inspection device of Patent Document 1, the inspection of whether the guide rail is within an appropriate range should be performed based on the behavior of the trolley. When the trolley is self-propelled, since various sensors for controlling the trolley's behavior (e.g., walking behavior) are installed on the trolley, existing sensors on the trolley can be used in the inspection to reduce costs when the inspection is based on the trolley's behavior. Furthermore, when the inspection is based on the trolley's behavior, the quality of the guide rail's position can be determined by considering the actual behavior of the trolley. Although there is an advantage to checking whether the guide rail is within an appropriate range based on the trolley's behavior, Patent Document 1 does not disclose a method for checking based on the trolley's behavior.

[0005] Therefore, the desired outcome is the realization of a track inspection device that can check whether the guide rail is positioned within an appropriate range based on the behavior of the trolley.

[0006] The disclosed track inspection device is a track inspection device equipped with a trolley. The trolley travels along a pair of travel tracks and a guide track in a travel direction. From a vertical perspective, the direction orthogonal to the travel direction is defined as the width direction. The pair of travel tracks are arranged parallel to each other in the width direction and have straight sections where the travel direction is straight and curved sections where the travel direction is curved. The guide track is provided at least in the curved sections and is arranged parallel to at least one of the pair of travel tracks at different positions in the vertical direction. The aforementioned trolley includes: a right front wheel and a left front wheel, arranged in the aforementioned width direction; a right rear wheel and a left rear wheel, positioned further rearward than the aforementioned right front wheel and the aforementioned left front wheel in the aforementioned travel direction, and arranged in the aforementioned width direction; and a guide wheel, wherein the aforementioned right front wheel and the aforementioned right rear wheel are configured to roll on one of the aforementioned travel tracks, namely the right track, and the aforementioned left front wheel and the aforementioned left rear wheel are configured to roll on the other of the aforementioned travel tracks, namely the left track, and the aforementioned guide wheel is configured to contact the aforementioned guide track from one side in the aforementioned width direction and roll. When the aforementioned trolley travels in the aforementioned straight section, the aforementioned right front wheel and... The aforementioned right rear wheel rolls in contact with the aforementioned right track, and the aforementioned left front wheel and the aforementioned left rear wheel roll in contact with the aforementioned left track. The aforementioned guide wheel separates from the aforementioned guide track. When the aforementioned trolley travels in the aforementioned curved section, one of the aforementioned combination of the aforementioned right front wheel and the aforementioned right rear wheel, and the aforementioned combination of the aforementioned left front wheel and the aforementioned left rear wheel, becomes a contact wheel that rolls in contact with the corresponding aforementioned travel track. The other of the aforementioned combination of the aforementioned right front wheel and the aforementioned right rear wheel, and the aforementioned combination of the aforementioned left front wheel and the aforementioned left rear wheel, becomes a separate wheel that separates from the corresponding aforementioned travel track. Furthermore, the aforementioned guide wheel rolls in contact with the aforementioned guide track. The aforementioned track inspection device further includes a determination unit, which performs contact period determination processing, curve entry period determination processing, and track inspection processing. The contact period determination processing determines the period when the aforementioned guide wheel contacts the aforementioned guide track, i.e., the contact period. The curve entry period determination processing determines the curve entry period, which is the period when the aforementioned right front wheel and the aforementioned left front wheel enter the aforementioned curve section from the aforementioned straight section. The track inspection processing determines whether the setting position of the aforementioned guide track is within an appropriate range based on the relationship between the aforementioned curve entry period and the aforementioned contact period.

[0007] In this configuration, when the trolley travels in a straight section, the guide wheel separates from the guide rail. When the trolley travels in a curved section, the guide wheel contacts the guide rail and rolls. Therefore, as the trolley moves from a straight section into a curved section, the guide wheel contacts the guide rail. When the guide rail is positioned within an appropriate range, the guide wheel contacts the guide rail in conjunction with the right and left front wheels of the trolley as they move from a straight section into a curved section. In this case, the timing of the guide wheel contacting the guide rail (the contact period) and the timing of the right and left front wheels moving from a straight section into a curved section (the curve entry period) are within a predetermined range. On the other hand, when the guide rail is not positioned within an appropriate range, the timing of the contact period and the curve entry period will be outside the predetermined range. According to this configuration, considering the relationship between the curve entry period and the contact period, it is possible to determine whether the guide rail is positioned within an appropriate range based on the timing of the curve entry period and the contact period. In this way, according to this configuration, the position of the guide rail can be checked based on the behavior of the trolley to see if it is within an appropriate range.

[0008] Further features and advantages of the track inspection device will become clear through the following description of its implementation with reference to the drawings. Simple Explanation of the Diagram

[0009] Figure 1 is a 3D view of the trolley. Figure 2 is a front view of the trolley. Figure 3 is a plan view of the trolley located in the straight section. Figure 4 is a plan view of the trolley located at the boundary between the straight section and the curved section. Figure 5 shows the trolley passing through the curved section in a time series format. Figure 6 is an illustration of the trolley's behavior when the guide rail is positioned within an appropriate range. Figure 7 is a graph showing the time variation of wheel rotation speed and output signal when the guide rail is positioned within an appropriate range. Figure 8 is an illustration of the behavior of the trolley when the guide rail is set in a position that deviates from the contact wheel in the width direction relative to an appropriate range. Figure 9 is a graph showing the time variation of the wheel's rotational speed and the output signal when the guide rail's position deviates from the contact wheel's side in the width direction relative to an appropriate range. Figure 10 is an illustration of the behavior of the trolley when the guide rail is set in a position that deviates from the appropriate range towards the side of the split wheels in the width direction. Figure 11 is a graph showing the time variation of the wheel rotation speed and output signal when the guide rail is set off from the appropriate range and deviates to the side of the separated wheel in the width direction. Figure 12 is a control block diagram. Implementation

[0010] Forms used to implement inventions

[0011] The implementation of the track inspection device is illustrated with reference to the diagrams. Furthermore, the various technical features of the track inspection device described below can also be applied to track inspection methods using the track inspection device, or to track inspection programs for controlling the track inspection device. Such methods or programs, as well as memory media (e.g., CDs, flash memory, etc.) storing such programs, are also disclosed in this specification.

[0012] As shown in Figures 1 and 2, the track inspection device 1 includes a trolley 10 (here, a self-propelled trolley 10), which travels along a pair of travel tracks 80 and a guide track 83 in the travel direction X. In Figure 1, the guide track 83 is omitted. The pair of travel tracks 80 and the guide track 83 are arranged along the travel path 70 of the trolley 10. From a vertical Z-angle (planar view) along the vertical direction Z, the direction orthogonal to the travel direction X is defined as the width direction Y. Here, the width direction Y is a horizontal direction orthogonal to the travel direction X.

[0013] In this embodiment, the track inspection device 1 is an article conveying device 100 used to transport article 2. Furthermore, the transport cart (article transport cart) that holds and transports article 2 is used as a trolley 10 for inspection, specifically to check whether the guide rail 83 is positioned within an appropriate range. That is, in this embodiment, the trolley 10 is a transport cart that holds and transports article 2. As shown in FIG1, in this embodiment, the trolley 10 is a ceiling transport cart that travels along a travel path 70, which is formed along the ceiling. Therefore, although the illustration is omitted, a pair of travel rails 80 and guide rails 83 (see FIG2) are, for example, suspended from the ceiling. Additionally, the trolley 10 can also be a transport cart other than a ceiling transport cart. Furthermore, the type of article 2 is not limited to this; article 2 can be, for example, a FOUP (Front Opening Unified Pod) for holding semiconductor wafers.

[0014] As shown in Figures 3 and 4, a pair of travel tracks 80 are arranged parallel to each other in the width direction Y. The pair of travel tracks 80 are arranged at the same position (i.e., at the same height) in the vertical direction Z. The pair of travel tracks 80 includes: a straight section 71 in the travel direction X and a curved section 72 in the travel direction X. That is, the travel path 70 includes a straight section 71 and a curved section 72. Both sides of the pair of travel tracks 80 are provided in the straight section 71. On the other hand, at least one of the pair of travel tracks 80 is provided in the curved section 72. Specifically, at least one of the pair of travel tracks 80 is provided in the curved section 72 for the contact wheel 20A described later to roll. Figures 3 and 4 illustrate the case where both sides of the pair of travel tracks 80 are provided in the curved section 72. In addition, although the curved section 72 shown in Figures 3 and 4 connects the ends of the two straight sections 71 to each other, the curved section 72 can also be configured to branch off from or merge into the straight section 71.

[0015] The guide rail 83 is provided at least in the curved section 72. In the examples shown in Figures 3 and 4, the guide rail 83 is provided throughout the entire area of ​​the curved section 72, and a portion of the boundary B (the boundary B between the straight section 71 and the curved section 72) in the straight section 71. From a vertical Z-view, the guide rail 83 is positioned between a pair of travel rails 80. Here, the guide rail 83 is positioned at the center of the width direction Y between the pair of travel rails 80 from a vertical Z-view (in other words, at the center of the width direction Y of the travel path 70).

[0016] The guide rail 83 is positioned at different locations in the vertical direction Z relative to the pair of travel rails 80. As shown in FIG2, in this embodiment, the guide rail 83 is positioned at the upper Z2 in the vertical direction Z relative to the pair of travel rails 80. Furthermore, the guide rail 83 is configured to be parallel to at least one of the pair of travel rails 80. In the straight section 71, the guide rail 83 is configured to be parallel to both of the pair of travel rails 80. When a pair of travel rails 80 is provided in the curved section 72, the guide rail 83 is configured to be parallel to both of the pair of travel rails 80. When only one of the pair of travel rails 80 is provided in the curved section 72 (specifically, the rail for the contact wheel 20A to roll in the pair of travel rails 80), the guide rail 83 is configured to be parallel to that one of the pair of travel rails 80.

[0017] As shown in Figure 1, the trolley 10 has a right front wheel 24 and a left front wheel 23 arranged in the width direction Y, and a right rear wheel 22 and a left rear wheel 21 arranged in the width direction Y. The right rear wheel 22 and the left rear wheel 21 are positioned further rearward (X2) than the right front wheel 24 and the left front wheel 23 in the travel direction X. The right front wheel 24 and the right rear wheel 22 are configured to roll on one of a pair of travel tracks 80 (specifically, the track on the right side facing the travel direction of the trolley 10), namely the right track 82, while the left front wheel 23 and the left rear wheel 21 are configured to roll on the other of the pair of travel tracks 80 (specifically, the track on the left side facing the travel direction of the trolley 10), namely the left track 81. In this way, the right track 82 is the travel track 80 corresponding to the combination of the right front wheel 24 and the right rear wheel 22, and the left track 81 is the travel track 80 corresponding to the combination of the left front wheel 23 and the left rear wheel 21. In this embodiment, one each of the left rear wheel 21, right rear wheel 22, left front wheel 23, and right front wheel 24 is provided.

[0018] The left rear wheel 21, right rear wheel 22, left front wheel 23, and right front wheel 24 are configured to rotate about an axis orthogonal to the vertical direction Z (in other words, about an axis along the width direction Y). Furthermore, the right front wheel 24 and right rear wheel 22 roll in contact with the surface of the right track 82 facing upward Z2 (which is a horizontal surface in this case), while the left front wheel 23 and left rear wheel 21 roll in contact with the surface of the left track 81 facing upward Z2 (which is a horizontal surface in this case).

[0019] As shown in Figure 1, in this embodiment, the trolley 10 includes a first traveling section 11 and a second traveling section 12. The second traveling section 12 is positioned at the front side X1 of the traveling direction X relative to the first traveling section 11. The right rear wheel 22 and the left rear wheel 21 are provided on the first traveling section 11, and the right front wheel 24 and the left front wheel 23 are provided on the second traveling section 12. The trolley 10 is positioned on the traveling path 70 with its front-rear direction L along the traveling direction X. The direction connecting the first axis A1 and the second axis A2 (described later) in the vertical Z-view (refer to Figures 3 and 4) is the front-rear direction L of the vehicle body. In the curved section 72, the trolley 10 is positioned on the traveling path 70 with its front-rear direction L along the tangent direction of the curved traveling direction X in the vertical Z-view (refer to Figure 4). Furthermore, as shown in Figure 1, the trolley 10 is positioned on the travel path 70 with its vertical direction (H) aligned with the vertical direction (Z). In this specification, "travel direction X" and "vertical direction Z" can be essentially referred to as "front-rear direction L" and "vertical direction H".

[0020] As shown in Figure 1, the trolley 10 includes a main body 13 connected to the first traveling section 11 and the second traveling section 12. In this embodiment, the main body 13 is positioned at the lower side Z1 in the vertical direction Z relative to the first traveling section 11 and the second traveling section 12, and is supported by the first traveling section 11 and the second traveling section 12. Although detailed description is omitted, the main body 13 includes a holding part for holding the article 2, and the article 2 is transported by the trolley 10 while being held by the holding part.

[0021] As shown in Figures 3 and 4, in this embodiment, the first traveling part 11 is rotatably connected to the main body 13 about a first axis A1 along the vertical direction Z, and the second traveling part 12 is rotatably connected to the main body 13 about a second axis A2 along the vertical direction Z. Therefore, as shown in Figure 5, when the trolley 10 travels sequentially through the straight section 71, the curved section 72, and another straight section 71, the posture of the first traveling part 11 or the second traveling part 12 (the posture about the axis along the vertical direction Z) can be appropriately changed, allowing the trolley 10 to travel smoothly. Furthermore, the first axis A1 and the second axis A2 are virtual axes; the first axis A1 is located at the center position in the width direction Y of the first traveling part 11, and the second axis A2 is located at the center position in the width direction Y of the second traveling part 12.

[0022] As shown in Figure 1, the trolley 10 is equipped with guide wheels 40. The guide wheels 40 are configured to roll against the guide rail 83 from one side in the width direction Y (see Figure 2). The guide wheels 40 are configured to rotate (free-spinning) about an axis in the vertical direction Z and roll against the surface of the guide rail 83 facing the width direction Y (the vertical surface). In this embodiment, guide wheels 40 are respectively provided on the first traveling section 11 and the second traveling section 12. Here, the guide wheel 40 provided on the first traveling section 11 is referred to as the rear guide wheel 41, and the guide wheel 40 provided on the second traveling section 12 is referred to as the front guide wheel 42. In this embodiment, both the rear guide wheel 41 and the front guide wheel 42 are arranged in twos in the traveling direction X.

[0023] As shown in Figures 3 and 4, in this embodiment, the first traveling unit 11 includes a right rear auxiliary wheel 52 and a left rear auxiliary wheel 51 arranged in the width direction Y, and the second traveling unit 12 includes a right front auxiliary wheel 54 and a left front auxiliary wheel 53 arranged in the width direction Y. The right rear auxiliary wheel 52, left rear auxiliary wheel 51, right front auxiliary wheel 54, and left front auxiliary wheel 53 are configured to roll upon contact with the traveling track 80 from one side in the width direction Y. The left rear auxiliary wheel 51, right rear auxiliary wheel 52, left front auxiliary wheel 53, and right front auxiliary wheel 54 are configured to rotate (in this case, idle) around an axis in the vertical direction Z. Furthermore, the right front auxiliary wheel 54 and the right rear auxiliary wheel 52 roll in contact with the surface of the right track 82 facing the center of the width direction Y (the side closest to the center of the width direction Y between a pair of travel tracks 80), which is a horizontal surface in this case. The left front auxiliary wheel 53 and the left rear auxiliary wheel 51 roll in contact with the surface of the left track 81 facing the center of the width direction Y, which is a horizontal surface in this case. In this way, the right track 82 is the travel track 80 corresponding to the combination of the right rear auxiliary wheel 52 and the right front auxiliary wheel 54, and the left track 81 is the travel track 80 corresponding to the combination of the left rear auxiliary wheel 51 and the left front auxiliary wheel 53. In this embodiment, the right rear auxiliary wheel 52, the left rear auxiliary wheel 51, the right front auxiliary wheel 54, and the left front auxiliary wheel 53 are all provided in pairs in the travel direction X.

[0024] When the trolley 10 travels in the straight section 71, the right front wheel 24 and the right rear wheel 22 will contact the right rail 82 and roll, and the left front wheel 23 and the left rear wheel 21 will contact the left rail 81 and roll. The guide wheel 40 will separate from the guide rail 83. As mentioned above, except for a part of the boundary B side in the straight section 71, there is no guide rail 83 in the straight section 71.

[0025] In this embodiment, when the trolley 10 travels in the straight section 71, the right rear auxiliary wheel 52 and the right front auxiliary wheel 54 (two right rear auxiliary wheels 52 and two right front auxiliary wheels 54 in this embodiment) will contact the right track 82 from the center side in the width direction Y, and the left rear auxiliary wheel 51 and the left front auxiliary wheel 53 (two left rear auxiliary wheels 51 and two left front auxiliary wheels 53 in this embodiment) will contact the left track 81 from the center side in the width direction Y. In this way, the rotation of the first traveling part 11 around the first axis A1 and the rotation of the second traveling part 12 around the second axis A2 are restricted by a pair of traveling tracks 80, so that the posture of the first traveling part 11 and the second traveling part 12 (that is, the posture of the trolley 10) is maintained in the posture of traveling along the pair of traveling tracks 80.

[0026] When the trolley 10 travels in the curve section 72, one of the combination of the right front wheel 24 and the right rear wheel 22 and the combination of the left front wheel 23 and the left rear wheel 21 will become the contact wheel 20A that rolls in contact with the corresponding travel track 80. The other combination of the right front wheel 24 and the right rear wheel 22 and the left front wheel 23 and the left rear wheel 21 will become the separating wheel 20B that separates from the corresponding travel track 80. Furthermore, the guide wheels 40 (in this embodiment, the rear guide wheel 41 and the front guide wheel 42) will roll in contact with the guide track 83. In Figures 3 and 4, and subsequently Figures 6, 8, and 10, the wheels that will become contact wheels 20A in the curve section 72 before entering the curve section 72 are marked with the symbol "20A", and the wheels that will become separating wheels 20B in the curve section 72 are marked with the symbol "20B".

[0027] When the trolley 10 travels in the curve section 72, the guide wheel 40 contacts the guide rail 83 from the side that allows the trolley 10 to maintain the position where the separating wheel 20B is separated from the travel rail 80 corresponding to the separating wheel 20B. In this embodiment, the guide rail 83 is positioned on the upper Z2 relative to a pair of travel rails 80. Therefore, as shown in FIG2, the guide wheel 40 contacts the guide rail 83 from the side of the contact wheel 20A in the width direction Y. As shown in FIG3, in this embodiment, in the curve section 72, not only is there a travel rail 80 corresponding to the contact wheel 20A (here, the left rail 81), but also a travel rail 80 corresponding to the separating wheel 20B (here, the right rail 82). In this embodiment, as shown in FIG2, in the curve section 72, a recess is formed on the upper surface of the travel track 80 (here, the right track 82) corresponding to the separating wheel 20B, thereby causing the separating wheel 20B to separate from the corresponding travel track 80 in the curve section 72.

[0028] In this embodiment, when the trolley 10 travels in the curved section 72, the guide wheel 40 contacts the guide rail 83, and the combination of the right rear auxiliary wheel 52 and the right front auxiliary wheel 54 or the combination of the left rear auxiliary wheel 51 and the left front auxiliary wheel 53 contacts the travel rail 80 corresponding to the contact wheel 20A. As shown in Figure 3, when the trolley 10 travels in the curved section 72, the guide wheel 40 contacts the guide rail 83, and the combination of the left rear auxiliary wheel 51 and the left front auxiliary wheel 53 contacts the left rail 81 (refer to Figures 2 and 4). The aforementioned curved section 72 is the curved section of the travel rail 80 corresponding to the contact wheel 20A that becomes the left rail 81. In this way, the rotation of the first traveling part 11 around the first axis A1 and the rotation of the second traveling part 12 around the second axis A2 are restricted by the traveling track 80 corresponding to the guide track 83 and the contact wheel 20A, so that the posture of the first traveling part 11 and the second traveling part 12 is maintained as a posture of traveling along a pair of traveling tracks 80.

[0029] In this embodiment, when the trolley 10 travels in the curved section 72, the combination of the right rear auxiliary wheel 52 and the right front auxiliary wheel 54, or the combination of the left rear auxiliary wheel 51 and the left front auxiliary wheel 53, will further contact the travel track 80 corresponding to the separating wheel 20B. As shown in FIG3, when the trolley 10 travels in the curved section 72, the combination of the right rear auxiliary wheel 52 and the right front auxiliary wheel 54 will contact the right track 82 (refer to FIG2 and FIG4), and the aforementioned curved section 72 is the curved section of the travel track 80 corresponding to the contact wheel 20A, which becomes the left track 81. Accordingly, the rotation of the first traveling part 11 around the first axis A1 and the rotation of the second traveling part 12 around the second axis A2 are also restricted by the travel track 80 corresponding to the separating wheel 20B.

[0030] In this embodiment, when the trolley 10 travels in the curved section 72, the combination of the right front wheel 24 and the right rear wheel 22, or the combination of the left front wheel 23 and the left rear wheel 21, will contact the travel track 80 located on the inner side (near the rotation center) in the width direction Y of the right track 82 and the left track 81. In other words, among the combinations of the right front wheel 24 and the right rear wheel 22 and the left front wheel 23 and the left rear wheel 21, the combination that forms the inner circle in the curved section 72 will become the contact wheel 20A, and the combination that forms the outer circle in the curved section 72 will become the separating wheel 20B. Furthermore, the guide wheel 40 contacts the guide track 83 from the inner side in the width direction Y. For example, as shown in Figure 3, when the trolley 10 travels in the curved section 72 (left curved section) on the inner side of the left track 81 relative to the right track 82 in the width direction Y, the combination of the left front wheel 23 and the left rear wheel 21, which form the inner circle, becomes the contact wheel 20A, and the combination of the right front wheel 24 and the right rear wheel 22, which form the outer circle, becomes the separating wheel 20B. Although the figure is omitted, when the trolley 10 travels in the curved section 72 (right curved section) on the inner side of the right track 82 relative to the left track 81 in the width direction Y, the combination of the right front wheel 24 and the right rear wheel 22, which form the inner circle, becomes the contact wheel 20A, and the combination of the left front wheel 23 and the left rear wheel 21, which form the outer circle, becomes the separating wheel 20B.

[0031] As shown in Figure 1, the first traveling unit 11 includes a first drive unit M1 (e.g., an electric motor such as a servo motor) that rotates the right rear wheel 22 and the left rear wheel 21 at the same speed, and the second traveling unit 12 includes a second drive unit M2 (e.g., an electric motor such as a servo motor) that rotates the right front wheel 24 and the left front wheel 23 at the same speed. The right rear wheel 22 and the left rear wheel 21 are formed with the same diameter. The first drive unit M1 drives the right rear wheel 22 and the left rear wheel 21 to rotate at the same speed, thereby causing the first traveling unit 11 to travel along a pair of traveling tracks 80. Similarly, the right front wheel 24 and the left front wheel 23 are formed with the same diameter. The second drive unit M2 drives the right front wheel 24 and the left front wheel 23 to rotate at the same speed, thereby causing the second traveling unit 12 to travel along a pair of traveling tracks 80. In addition, the configuration of the trolley 10 is not limited to this. It can also be configured such that, for example, the second traveling part 12 does not have a second driving part M2, so that the right front wheel 24 and the left front wheel 23 spin freely.

[0032] As shown in Figure 1, in this embodiment, the first traveling unit 11 includes a third drive unit M3 (e.g., a solenoid or electric motor) that moves the rear guide wheel 41 in the width direction Y, and the second traveling unit 12 includes a fourth drive unit M4 (e.g., a solenoid or electric motor) that moves the front guide wheel 42 in the width direction Y. Regardless of whether the curve section 72 is a left curve section or a right curve section, the positions of the rear guide wheel 41 and the front guide wheel 42 in the width direction Y can be switched to a position where they contact the guide rail 83 from the inside of the width direction Y by driving the third drive unit M3 and the fourth drive unit M4.

[0033] As shown in Figure 12, the track inspection device 1 includes a control unit 60. The various functions of the control unit 60 can be achieved through the cooperation of hardware such as a computing processing unit and a program running on that hardware. The control unit 60 can be installed on the trolley 10 or installed independently of the trolley 10. Alternatively, a portion of the control unit 60 can be installed on the trolley 10, while the remaining parts of the control unit 60 can be installed independently of the trolley 10.

[0034] The control unit 60 controls the movement of the vehicle 10. In this embodiment, the control unit 60 controls the movement of the first traveling unit 11 and the second traveling unit 12. Specifically, the control unit 60 controls the movement of the first traveling unit 11 by controlling the drive of the first drive unit M1, and controls the movement of the second traveling unit 12 by controlling the drive of the second drive unit M2.

[0035] Furthermore, when the trolley 10 enters the curved section 72 from the straight section 71, the control unit 60 controls the drive of the third drive unit M3 and the fourth drive unit M4, thereby switching the position of the rear guide wheel 41 and the front guide wheel 42 in the width direction Y according to the structure of the curved section 72. Specifically, when the curved section 72 entering the destination is a left-hand curved section (see Figure 3), the control unit 60 moves the rear guide wheel 41 and the front guide wheel 42 to the left (to the left of the trolley 10's direction of travel). When the curved section 72 entering the destination is a right-hand curved section, the control unit 60 moves the rear guide wheel 41 and the front guide wheel 42 to the right (to the right of the trolley 10's direction of travel), thereby switching the position of the rear guide wheel 41 and the front guide wheel 42 in the width direction Y to a position where they contact the guide rail 83 from the inside of the width direction Y.

[0036] In this embodiment, the control unit 60 is configured to control the rotational speeds of the right rear wheel 22 and the left rear wheel 21 to match a target rotational speed, thereby causing the first traveling unit 11 to travel. Specifically, the control unit 60 generates a drive command and outputs the drive command to the first drive unit M1. The drive command is used to match the rotational speeds of the right rear wheel 22 and the left rear wheel 21 to the target rotational speed. This drive command is either a speed command or a position command. The position command is generated, for example, by integrating the speed command. The first drive unit M1 includes: a motor unit that rotates the right rear wheel 22 and the left rear wheel 21; and an amplifier unit that drives the motor unit to follow the drive command input by the control unit 60 through feedback control. The first drive unit M1 rotates the right rear wheel 22 and the left rear wheel 21 in a manner that matches the rotational speeds of the right rear wheel 22 and the left rear wheel 21 to the target rotational speed.

[0037] In this embodiment, the control unit 60 is configured to cause the second traveling unit 12 to travel in a manner driven by the first traveling unit 11. That is, the control unit 60 controls the drive state of the second driving unit M2 on the right front wheel 24 and left front wheel 23 in a driven manner according to the drive state of the first drive unit M1 on the right rear wheel 22 and left rear wheel 21, thereby causing the second traveling unit 12 to travel in a manner driven by the first traveling unit 11. For example, the control unit 60 controls the drive torque of the second drive unit M2 on the right front wheel 24 and left front wheel 23, so that the second traveling unit 12 travels in a manner driven by the first traveling unit 11. The control unit 60 may also control the drive torque of the second drive unit M2 on the right front wheel 24 and left front wheel 23 to be zero (no torque control), thereby causing the second traveling unit 12 to travel in a manner driven by the first traveling unit 11.

[0038] In this embodiment, the track inspection device 1 includes a measuring unit S, which measures the rotational speed of the right front wheel 24 and the left front wheel 23, or a speed proportional to that rotational speed, and the rotational speed of the right rear wheel 22 and the left rear wheel 21, or a speed proportional to that rotational speed. That is, the track inspection device 1 includes a measuring unit S, which measures the rotational speed of the right front wheel 24 and the left front wheel 23, or a speed proportional to that rotational speed, and also measures the rotational speed of the right rear wheel 22 and the left rear wheel 21, or a speed proportional to that rotational speed. In the example shown in Figure 12, a first measuring unit S1 (e.g., an encoder) is provided in the first drive unit M1 to measure the rotational speed of the right rear wheel 22 and the left rear wheel 21, or a speed proportional to that rotational speed. Similarly, a second measuring unit S2 (e.g., an encoder) is provided in the second drive unit M2 to measure the rotational speed of the right front wheel 24 and the left front wheel 23, or a speed proportional to that rotational speed. The track inspection device 1 uses these first measuring units S1 and second measuring units S2 as measuring units S. That is, the track inspection device 1 has measuring units S including the first measuring unit S1 and the second measuring unit S2. As described above, the first drive unit M1 is configured to perform feedback control, and the first measuring unit S1 is provided in the first drive unit M1 to obtain feedback values ​​used in this feedback control.

[0039] Furthermore, during the period from when the trolley 10 enters the curved section 72 with a certain curvature as shown in Figure 3 until it exits, the posture of the trolley 10 changes sequentially as shown in Figure 5: posture 0 P0, posture 1 P1, posture 2 P2, posture 3 P3, posture 4 P4, posture 5 P5, posture 6 P6, and posture 7 P7. In the following, although the postures of the trolley 10 are defined based on the positions of the left front auxiliary wheel 53 and the left rear auxiliary wheel 51, the postures of the trolley 10 can also be defined by replacing the left front auxiliary wheel 53 and the left rear auxiliary wheel 51 with the right front auxiliary wheel 54 and the right rear auxiliary wheel 52.

[0040] Position 0 P0 is the position of the trolley 10 at the point in time when the front left auxiliary wheel 53 of the two left front auxiliary wheels 53 reaches the first boundary B1. As shown in Figure 3, the first boundary B1 is the boundary B between the curve section 72 and the straight section 71 on the rear X2 relative to the curve section 72. The second boundary B2, described later, is the boundary B between the curve section 72 and the straight section 71 on the front X1 relative to the curve section 72. Position 1 P1 is the position of the trolley 10 at the point in time when the rear left front auxiliary wheel 53 of the two left front auxiliary wheels 53 reaches the first boundary B1. Position 2 P2 is the position of the trolley 10 at the point in time when the front left rear auxiliary wheel 51 of the two left rear auxiliary wheels 51 reaches the first boundary B1. Position 3 P3 is the position of the trolley 10 at the point in time when the rear left rear auxiliary wheel 51 of the two left rear auxiliary wheels 51 reaches the first boundary B1.

[0041] Posture 4, P4, is the posture of carriage 10 at the point when the front left auxiliary wheel 53 (X1) of the two left front auxiliary wheels 53 reaches the second boundary B2. Posture 5, P5, is the posture of carriage 10 at the point when the rear left front auxiliary wheel 53 (X2) of the two left front auxiliary wheels 53 reaches the second boundary B2. Posture 6, P6, is the posture of carriage 10 at the point when the front left rear auxiliary wheel 51 (X1) of the two left rear auxiliary wheels 51 reaches the second boundary B2. Posture 7, P7, is the posture of carriage 10 at the point when the rear left rear auxiliary wheel 51 (X2) of the two left rear auxiliary wheels 51 reaches the second boundary B2.

[0042] When the trolley 10 enters the curve section 72 from the straight section 71, the posture of the trolley 10 changes from posture 0 P0 to posture 1 P1 as the right front wheel 24 and left front wheel 23 enter the curve section 72. With this change in posture, the difference between the front wheel rotation speed VF (the rotation speed of the right front wheel 24 and left front wheel 23) and the rear wheel rotation speed VR (the rotation speed of the right rear wheel 22 and left rear wheel 21), i.e., the front-rear wheel speed difference VD, changes from a value close to zero to a value determined by the curvature of the curve section 72. Here, the value of subtracting the rear wheel rotation speed VR from the front wheel rotation speed VF, divided by the rear wheel rotation speed VR, is taken as the front-rear wheel speed difference VD. In this embodiment, since the inner wheel of the right front wheel 24 and the left front wheel 23 will contact the corresponding travel track 80 and roll, as shown in the lower part of Figure 7, as the posture of the trolley 10 changes from posture 0 P0 to posture 1 P1, the rotational speed VF of the front wheel will decrease relative to the rotational speed VR of the rear wheel.

[0043] The lower part of Figure 7 shows an example of the temporal changes in the front wheel rotational speed VF, rear wheel rotational speed VR, and the front-to-rear wheel speed difference VD when the trolley 10 travels along the path 70, which includes the curve section 72 (the same applies in Figures 9 and 11 referred to later). Figure 7 shows the situation when the trolley 10 enters the curve section 72 with the rear wheel rotational speed VR controlled at the second speed V2. After the right front wheel 24 and left front wheel 23 enter the curve section 72 from the straight section 71, i.e., the curve entry period T2, while the rear wheel rotational speed VR remains at the second speed V2, the front wheel rotational speed VF decreases from the second speed V2 to a speed close to the first speed V1. Accompanying this, after the curve entry period T2, the front-to-rear wheel speed difference VD increases from a value of zero or close to zero (specifically, it increases towards the negative side). Here, the signal output when the front-to-rear wheel speed difference VD exceeds a negative first threshold on the negative side is designated as the first output signal G1, and the signal output when the front-to-rear wheel speed difference VD exceeds a positive second threshold on the positive side is designated as the second output signal G2. The upper graph of Figure 7 shows an example of the time variation of the first output signal G1 and the second output signal G2, and also shows the signal with the output value of "1" (the same is true in Figures 9 and 11 referred to later).

[0044] As described above, after the front and rear wheel speed difference VD increases from zero or near zero towards the negative side, the posture of the trolley 10 changes from posture 2 P2 to posture 3 P3 as the right rear wheel 22 and left rear wheel 21 enter the curve section 72. With this posture change of the trolley 10, the front and rear wheel speed difference VD decreases to zero or near zero. In Figure 7, to minimize the speed change at the center of the trolley 10 in the width direction Y, the rear wheel rotational speed VR is reduced from the second speed V2 to the first speed V1 during the change of the trolley 10's posture from posture 2 P2 to posture 3 P3. Then, during the change of the trolley 10's posture from posture 3 P3 to posture 4 P4, the rear wheel rotational speed VR remains at the first speed V1.

[0045] As the trolley 10 enters the straight section 71 from the curve section 72, the posture of the trolley 10 changes from posture 4 P4 to posture 5 P5 as the right front wheel 24 and left front wheel 23 enter the straight section 71. With this change in posture, the front wheel rotational speed VF increases relative to the rear wheel rotational speed VR. In the example shown in Figure 7, with the rear wheel rotational speed VR maintained at the first speed V1, the front wheel rotational speed VF increases from the first speed V1 to a speed close to the second speed V2. Simultaneously, the front-to-rear wheel speed difference VD increases from zero or near zero (specifically, it increases towards the positive side).

[0046] As described above, after the front and rear wheel speed difference VD increases from zero or near zero towards the positive side, the posture of the trolley 10 changes from posture 6 P6 to posture 7 P7 as the right rear wheel 22 and left rear wheel 21 enter the straight section 71. With this change in posture of the trolley 10, the front and rear wheel speed difference VD decreases to zero or near zero. In Figure 7, in order to minimize the speed change at the center of the trolley 10 in the width direction Y, the rear wheel rotational speed VR is increased from the first speed V1 to the second speed V2 during the change in posture of the trolley 10 from posture 6 P6 to posture 7 P7.

[0047] Next, we will explain the inspection of whether the setting position of the guide rail 83 is within an appropriate range. As shown in FIG12, the rail inspection device 1 includes a determination unit 61, which performs contact period determination processing, curve entry period determination processing, and rail inspection processing. As described above, in this embodiment, the trolley 10 included in the rail inspection device 1 is a transport vehicle that holds and transports the item 2, and the determination unit 61 performs contact period determination processing, curve entry period determination processing, and rail inspection processing, for example, during the movement of the transport vehicle.

[0048] The determination unit 61 includes a contact period determination unit 62 that performs contact period determination processing, a curve entry period determination unit 63 that performs curve entry period determination processing, and a track inspection unit 64 that performs track inspection processing. These multiple functional units of the determination unit 61 are configured to exchange information with each other. Furthermore, these multiple functional units are at least logically distinct, but do not necessarily need to be physically distinct.

[0049] In this embodiment, the control unit 60 includes a determination unit 61. The arithmetic processing device of the control unit 60 executes the programs stored in the memory unit, thereby realizing the functions of the contact period determination unit 62 (contact period determination function), the curve entry period determination unit 63 (curve entry period determination function), and the track inspection unit 64 (track inspection function).

[0050] The contact period determination process is the process of determining the period when the guide wheel 40 contacts the guide rail 83, i.e., the contact period T1. Since the guide wheel 40 separates from the guide rail 83 when the trolley 10 is traveling in the straight section 71, and contacts the guide rail 83 and rolls when the trolley 10 is traveling in the curved section 72, the guide wheel 40 will contact the guide rail 83 during the process of the trolley 10 moving from the straight section 71 to the curved section 72. In this embodiment, the contact period T1 is determined based on the vibration of the front wheel rotation speed VF caused by the impact of the guide wheel 40 (specifically the front guide wheel 42) contacting the guide rail 83.

[0051] Specifically, in this embodiment, the track inspection device 1 includes a measuring unit S, which measures the rotational speed of the right front wheel 24 and the left front wheel 23, or a speed proportional to that rotational speed. Furthermore, in the contact period determination process, the period during which vibrations of the front wheel rotational speed VF or a speed proportional to the front wheel rotational speed VF, detected by the measuring unit S, occur (e.g., the period when vibrations begin to occur) is determined as the contact period T1 (see Figures 9 and 11). Thus, in this embodiment, the determination unit 61 (specifically, the contact period determination unit 62) determines the period during which vibrations of the speeds detected by the measuring unit S occur as the contact period T1.

[0052] The cornering entry period determination process involves determining the cornering entry period T2. The aforementioned cornering entry period T2 is the period when the right front wheel 24 and the left front wheel 23 enter the cornering section 72 from the straight section 71. As mentioned above, after the right front wheel 24 and the left front wheel 23 enter the cornering section 72 from the straight section 71, i.e., after cornering entry period T2, the front-rear wheel speed difference VD will increase from zero or near zero towards the negative or positive side. In this embodiment, after cornering entry period T2, the front-rear wheel speed difference VD will increase from zero or near zero towards the negative side. In this embodiment, the cornering entry period T2 is determined based on the increased front-rear wheel speed difference VD after cornering entry period T2.

[0053] Specifically, in this embodiment, the track inspection device 1 includes a measuring unit S, which measures the rotational speed of the right front wheel 24 and the left front wheel 23, or a speed proportional to that rotational speed, and the rotational speed of the right rear wheel 22 and the left rear wheel 21, or a speed proportional to that rotational speed. Furthermore, in the cornering entry period determination process, the period when the front-rear wheel speed difference VD has reached a predetermined value or higher based on the detection results of the measuring unit S is determined as the cornering entry period T2 (see Figure 7). In this embodiment, the period when the front-rear wheel speed difference VD has reached a predetermined value or higher on the negative side is determined as the cornering entry period T2. That is, the period when the first output signal G1 is output is determined as the cornering entry period T2. In this embodiment, the determination unit 61 determines the period when the front and rear wheel speed difference VD has reached a predetermined value or above as the curve entry period T2. The aforementioned front and rear wheel speed difference VD is based on the difference between the rotational speeds of the right front wheel 24 and the left front wheel 23 and the rotational speeds of the right rear wheel 22 and the left rear wheel 21, as detected by the measurement unit S.

[0054] In Figure 7, the difference between the rotational speeds of the right front wheel 24 and the left front wheel 23 and the right rear wheel 22 and the left rear wheel 21 is shown by a lighter dashed line as the front-to-rear wheel speed difference VD, and the value after removing the high-frequency components from this difference is shown by a darker dashed line (the same applies in Figures 9 and 11 referred to later). In order to more appropriately determine the cornering entry time T2, it is ideal to set the following configuration: the determination unit 61 uses the value after removing the high-frequency components from the difference between the rotational speeds of the right front wheel 24 and the left front wheel 23 and the right rear wheel 22 and the left rear wheel 21 as the front-to-rear wheel speed difference VD, and performs cornering entry time determination processing.

[0055] As shown in Figure 6, in this embodiment, the portion of the guide track 83 located in the curved section 72 has a guide surface 83B on the side in the width direction Y where the guide wheel 40 contacts (in this embodiment, the inner side in the width direction Y), which has a curved shape along the curved section 72 from a vertical direction Z-view. Furthermore, in this embodiment, the portion of the guide track 83 located in the straight section 71 has a conical surface 83A on the side in the width direction Y where the guide wheel 40 contacts (in this embodiment, the inner side in the width direction Y), which is inclined relative to the travel direction X from a vertical direction Z-view. From a vertical direction Z-view, the conical surface 83A is inclined such that as it moves away from the boundary B towards the travel direction X, it faces the side separating from the movement trajectory of the guide wheel 40 (in this embodiment, the outer side in the width direction Y (the side separating from the rotation center)). By having a tapered surface 83A like this, as shown in FIG8, when the position of the guide rail 83 deviates from the appropriate range to one side of the width direction Y (in this embodiment, the inside of the width direction Y), the guide wheel 40 can be guided to the guide surface 83B by the action of the tapered surface 83A.

[0056] The track inspection process determines whether the guide track 83 is positioned within an appropriate range based on the relationship between the curve entry time T2 and the contact time T1. As mentioned above, in this embodiment, the guide track 83 is positioned on the upper Z2 relative to a pair of travel tracks 80. Therefore, as shown in FIG8, when the position of the guide track 83 deviates from the appropriate range towards the contact wheel 20A in the width direction Y (in the example shown in FIG8, the inner side of the width direction Y), the guide wheel 40 (in this embodiment, the front guide wheel 42) will contact the conical surface 83A of the guide track 83 (refer to the front guide wheel 42 shown by the dashed line in FIG8) at a time point earlier than the time when the right front wheel 24 and the left front wheel 23 reach the boundary B. As a result, as shown in FIG9, the contact time T1 is earlier than the curve entry time T2. As the position of the guide track 83 moves towards the contact wheel 20A in the width direction Y, the contact time T1 becomes earlier than the curve entry time T2.

[0057] Regarding the relationship between the curve entry period T2 and the contact period T1, in this embodiment, the configuration is as follows: during track inspection, if the contact period T1 occurs before the curve entry period T2 and exceeds a predetermined judgment range, it is determined that the position of the guide rail 83 is deviated from the contact wheel 20A in the width direction Y relative to an appropriate range. Furthermore, as shown in FIG9, high-frequency components are removed from the difference between the front wheel rotation speed VF and the rear wheel rotation speed VR, thereby removing (or substantially removing) the vibration of the front wheel rotation speed VF from the front-rear wheel speed difference VD. This vibration is caused by the impact of the guide wheel 40 contacting the guide rail 83 (specifically, the conical surface 83A). Therefore, the curve entry period T2 can be more appropriately determined based on the first output signal G1. Furthermore, since the first output signal G1 shown in Figure 9 corresponds to the front-to-rear wheel speed difference VD before removing the high-frequency components, the first output signal G1 will be output not only during the cornering entry period T2, but also during the contact period T1. However, the value after removing the high-frequency components from the difference between the front wheel rotation speed VF and the rear wheel rotation speed VR can be used as the front-to-rear wheel speed difference VD, thereby preventing the first output signal G1 from being output during the contact period T1, but instead outputting it during the cornering entry period T2.

[0058] On the other hand, as shown in Figure 6, when the guide rail 83 is positioned within an appropriate range, and the right front wheel 24 and left front wheel 23 reach boundary B, the guide wheel 40 (in this embodiment, the front guide wheel 42) will contact the guide rail 83 (refer to the front guide wheel 42 shown by the dashed line in Figure 6). Accordingly, when the guide rail 83 is positioned within an appropriate range, the timing relationship between the contact period T1 and the cornering entry period T2 will be within a specified range. In this embodiment, when the guide rail 83 is positioned within an appropriate range, as shown in Figure 7, the contact period T1 and the cornering entry period T2 are of the same duration. Furthermore, as shown in Figure 6, when the guide wheel 40 contacts the boundary portion of the conical surface 83A and the guide surface 83B in the guide rail 83, as shown in Figure 7, the vibration of the front wheel rotation speed VF caused by the impact of the guide wheel 40 contacting the guide rail 83 will be smaller. When the vibration of the front wheel rotation speed VF caused by the impact of the guide wheel 40 contacting the guide rail 83 is very small, and when it is impossible to distinguish the vibration of the front wheel rotation speed VF accompanying the contact of the guide wheel 40 with the guide rail 83 from the change of the front wheel rotation speed VF accompanying the entry of the right front wheel 24 and the left front wheel 23 into the curve section 72 (in other words, they cannot be separated), it can be configured, for example, that the determination unit 61 determines the same period as the curve entry period T2 as the contact period T1.

[0059] In this embodiment, the guide rail 83 is positioned on the upper Z2 relative to the pair of travel rails 80. Therefore, as shown in FIG10, when the position of the guide rail 83 deviates from the side of the split wheel 20B in the width direction Y (in the example shown in FIG10, the outer side of the width direction Y) relative to an appropriate range, the guide wheel 40 (in this embodiment, the front guide wheel 42) will contact the guide surface 83B of the guide rail 83 (refer to the front guide wheel 42 shown by the dashed line in FIG10) at a time later than the time when the right front wheel 24 and the left front wheel 23 have reached the boundary B. Therefore, although the contact period T1 is a later period relative to the curve entry period T2, in this embodiment, the determination of the curve entry period T2 is based on the change in the behavior of the trolley 10 caused by the guiding effect of the guide rail 83 on the guide wheel 40 (specifically, the change in the speed difference VD between the front and rear wheels). Therefore, in this embodiment, even if the guide rail 83 is offset from the side of the split wheel 20B in the width direction Y relative to an appropriate range, the curve entry period T2 and the contact period T1 can still be determined to be the same as when the guide rail 83 is within an appropriate range.

[0060] Focusing on the relationship between the curve entry period T2 and the contact period T1, this embodiment is configured such that, during track inspection processing, if the difference between the contact period T1 and the curve entry period T2 is within a predetermined judgment range, it is determined that the setting position of the guide rail 83 is within an appropriate range, or that the setting position of the guide rail 83 is deviated from the appropriate range towards the side of the separating wheel 20B in the width direction Y. The size of this judgment range can be, for example, the same as the aforementioned judgment range.

[0061] Furthermore, as mentioned above, when the guide rail 83 is positioned within an appropriate range, the vibration in the front wheel rotation speed VF caused by the impact of the guide wheel 40 contacting the guide rail 83 is relatively small. On the other hand, when the guide rail 83 is positioned deviated from the appropriate range towards the side of the split wheel 20B in the width direction Y, as shown in FIG10, when the front guide wheel 42 on the front side X1 contacts the guide surface 83B, the second traveling part 12 swings around the second axis A2 due to the existence of the gap 3 formed between the front guide wheel 42 on the rear side X2 and the guide surface 83B. As a result, compared with the case where the guide rail 83 is positioned within an appropriate range, a larger vibration occurs in the front wheel rotation speed VF (see FIG10). In view of this, it can also be configured as follows: In the track inspection process, when the difference between the contact period T1 and the curve entry period T2 is within a predetermined judgment range, and when the magnitude of the vibration of the front wheel rotation speed VF is above a specified threshold, it is determined that the setting position of the guide track 83 is deviated from the side of the split wheel 20B in the width direction Y relative to an appropriate range; when the magnitude of the vibration of the front wheel rotation speed VF is less than the threshold, it is determined that the setting position of the guide track 83 is within an appropriate range.

[0062] [Other implementation forms] Next, other implementations of the track inspection device will be described.

[0063] (1) In the above embodiment, the following configuration is used as an example: the track inspection device 1 includes a measuring unit S, which measures the rotational speed of the right front wheel 24 and the left front wheel 23 or a speed proportional to the rotational speed, and the determination unit 61 determines the period of vibration of the speed detected by the measuring unit S as the contact period T1. However, this disclosure is not limited to such a configuration, and it can also be configured as follows: the track inspection device 1 determines the contact period T1 based on the detection result of the rotational speed of the guide wheel 40 (specifically the front guide wheel 42) or the detection result of the vibration of the trolley 10, etc.

[0064] (2) In the above embodiment, the following configuration is used as an example: The track inspection device 1 includes a measuring unit S, which measures the rotational speed of the right front wheel 24 and the left front wheel 23 or a speed proportional to the rotational speed, and the rotational speed of the right rear wheel 22 and the left rear wheel 21 or a speed proportional to the rotational speed. The determination unit 61 determines the period when the speed difference VD between the front and rear wheels has reached a predetermined value or above as the curve entry period T2. The speed difference VD between the front and rear wheels is the difference between the rotational speeds of the right front wheel 24 and the left front wheel 23 and the right rear wheel 22 and the left rear wheel 21, based on the detection results of the measuring unit S. However, this disclosure is not limited to such a configuration. It can be configured, for example, as follows: the period when the trolley 10 (specifically, the detection device installed on the trolley 10) has detected the object to be detected at the position corresponding to the first boundary B1 is determined as the curve entry period T2, or the curve entry period T2 is determined based on the current estimated position of the trolley 10, i.e., the estimated current position. The estimated current position of the trolley 10 can be derived based on, for example, the travel distance of the trolley 10 (e.g., the travel distance measured using a rotary encoder). The aforementioned travel distance of the trolley 10 is the travel distance calculated from the information holding body that holds the address information (information showing the position along the travel direction X) read from the trolley 10 (specifically, the information holding the position information that is displayed by the reading device installed on the trolley 10).

[0065] In this way, without determining the curve entry period T2 based on the change in the behavior of the trolley 10 caused by the guiding effect of the guide rail 83 on the guide wheel 40 (specifically, the change in the speed difference VD between the front and rear wheels), the determination can also be configured to be performed in the track inspection process as follows. Specifically, in the track inspection process, if the difference between the contact period T1 and the curve entry period T2 is within a predetermined determination range, it is determined that the setting position of the guide rail 83 is within an appropriate range. If the contact period T1 is after the curve entry period T2 and exceeds the predetermined determination range, it is determined that the setting position of the guide rail 83 is deviated from the appropriate range towards the side of the separating wheel 20B in the width direction Y.

[0066] (3) In the above embodiment, the following configuration is used as an example: in the combination of the right front wheel 24 and the right rear wheel 22 and the combination of the left front wheel 23 and the left rear wheel 21, the combination that forms the inner ring in the curve section 72 becomes the contact wheel 20A, and the combination that forms the outer ring in the curve section 72 becomes the separating wheel 20B. However, this disclosure is not limited to that configuration, and it can also be configured as follows: in the combination of the right front wheel 24 and the right rear wheel 22 and the combination of the left front wheel 23 and the left rear wheel 21, the combination that forms the outer ring in the curve section 72 becomes the contact wheel 20A, and the combination that forms the inner ring in the curve section 72 becomes the separating wheel 20B. In this case, similar to the above embodiment, when the guide rail 83 is arranged on the upper Z2 relative to a pair of travel rails 80, the guide wheel 40 contacts the guide rail 83 from the outside in the width direction Y.

[0067] (4) In the above embodiment, the configuration in which the guide rail 83 is arranged on the upper side Z2 relative to the pair of travel rails 80 is described as an example. However, this disclosure is not limited to that configuration, and it can also be configured as follows: the guide rail 83 is arranged on the lower side Z1 relative to the pair of travel rails 80. For example, it can be configured as follows: when the main body 13 is arranged on the upper side Z2 relative to the first travel part 11 and the second travel part 12, unlike the above embodiment, the guide rail 83 can be arranged on the lower side Z1 relative to the pair of travel rails 80. When the guide rail 83 is arranged on the lower side Z1 relative to the pair of travel rails 80, unlike the above embodiment, the guide wheel 40 contacts the guide rail 83 from the side of the separating wheel 20B in the width direction Y. Therefore, in this case, it is more ideal to configure the track as follows: during track inspection, if the contact period T1 is before the curve entry period T2 and exceeds a predetermined judgment range, it is determined that the position of the guide rail 83 is deviated from the side of the separating wheel 20B in the width direction Y relative to an appropriate range. Furthermore, it is more ideal to configure the track as follows: during track inspection, if the difference between the contact period T1 and the curve entry period T2 is within a predetermined judgment range, it is determined that the position of the guide rail 83 is within an appropriate range, or that the position of the guide rail 83 is deviated from the side of the contact wheel 20A in the width direction Y relative to an appropriate range.

[0068] Alternatively, if the determination of the curve entry period T2 is not based on the change in the behavior of the trolley 10 caused by the guiding effect of the guide rail 83 on the guide wheel 40 (specifically, the change in the speed difference VD between the front and rear wheels), the determination can be made in the track inspection process as follows. Specifically, in the track inspection process, if the difference between the contact period T1 and the curve entry period T2 is within a predetermined determination range, it is determined that the setting position of the guide rail 83 is within an appropriate range. If the contact period T1 is after the curve entry period T2 and exceeds the predetermined determination range, it is determined that the setting position of the guide rail 83 is deviated from the appropriate range towards the contact wheel 20A in the width direction Y.

[0069] (5) In the above embodiment, the following configuration is used as an example: the guide rail 83 is positioned at the center of the width direction Y between the pair of travel rails 80 from a vertical Z-view. However, this disclosure is not limited to that configuration, and it can also be configured such that, from a vertical Z-view, the guide rail 83 is positioned inside or outside the width direction Y relative to the center of the width direction Y between the pair of travel rails 80. In this case, it can also be configured such that, unlike the above embodiment, the position of the guide wheel 40 (rear guide wheel 41 and front guide wheel 42 in the above embodiment) in the width direction Y is fixed at the center of the width direction Y.

[0070] (6) In the above embodiment, the example is described using a trolley 10 as a transport vehicle for holding and transporting the item 2. However, this disclosure is not limited to that configuration, and it may also be configured as follows: the track inspection device 1 has a dedicated trolley 10 for inspection, and the aforementioned inspection is an inspection of whether the setting position of the guide track 83 is within an appropriate range.

[0071] (7) Furthermore, the configurations disclosed in the above embodiments can be combined with those disclosed in other embodiments, provided there are no contradictions (including combinations of embodiments described as other embodiments with each other). Regarding other configurations, the embodiments disclosed in this specification are merely illustrative in all respects. Therefore, various changes can be made appropriately without departing from the spirit of this disclosure.

[0072] [Summary of the above implementation methods] The following is a summary of the track inspection device described above.

[0073] A track inspection device includes a trolley that travels along a pair of travel tracks and a guide track in a travel direction. From a vertical perspective, the direction orthogonal to the travel direction is defined as the width direction. The pair of travel tracks are arranged parallel to each other in the width direction and include a straight section where the travel direction is linear and a curved section where the travel direction is curved. The guide track is at least located in the curved section and is arranged parallel to at least one of the travel tracks at different vertical positions relative to the pair of travel tracks. The trolley includes: a right front wheel and a left front wheel arranged in the aforementioned width direction; a right rear wheel and a left rear wheel positioned further rearward than the aforementioned right front wheel and the aforementioned left front wheel in the aforementioned travel direction, and arranged in the aforementioned width direction; and a guide wheel. The aforementioned right front wheel and the aforementioned right rear wheel are configured to roll on one of the aforementioned travel tracks, namely the right track, and the aforementioned left front wheel and the aforementioned left rear wheel are configured to roll on the other of the aforementioned travel tracks, namely the left track. The aforementioned guide wheel is configured to contact the aforementioned guide track from one side in the aforementioned width direction and roll. When the trolley travels in the aforementioned straight section, the aforementioned right front wheel and the left rear wheel... The right rear wheel rolls in contact with the aforementioned right track, and the aforementioned left front wheel and left rear wheel roll in contact with the aforementioned left track. The aforementioned guide wheel separates from the aforementioned guide track. When the aforementioned trolley travels in the aforementioned curved section, one of the combination of the aforementioned right front wheel and the aforementioned right rear wheel, and the combination of the aforementioned left front wheel and the aforementioned left rear wheel, becomes a contact wheel that rolls in contact with the corresponding aforementioned travel track. The other of the combination of the aforementioned right front wheel and the aforementioned right rear wheel, and the combination of the aforementioned left front wheel and the aforementioned left rear wheel, becomes a separating wheel that separates from the corresponding aforementioned travel track. Furthermore, the aforementioned guide wheel rolls in contact with the aforementioned guide track. The track inspection device further includes a determination unit, which performs contact period determination processing, curve entry period determination processing, and track inspection processing. The contact period determination processing determines the period when the guide wheel contacts the guide track, i.e., the contact period. The curve entry period determination processing determines the curve entry period, which is the period when the right front wheel and the left front wheel enter the curve section from the straight section. The track inspection processing determines whether the guide track is positioned within an appropriate range based on the relationship between the curve entry period and the contact period.

[0074] In this configuration, when the trolley travels in a straight section, the guide wheel separates from the guide rail. When the trolley travels in a curved section, the guide wheel contacts the guide rail and rolls. Therefore, as the trolley moves from a straight section into a curved section, the guide wheel contacts the guide rail. When the guide rail is positioned within an appropriate range, the guide wheel contacts the guide rail in conjunction with the right and left front wheels of the trolley as they move from a straight section into a curved section. In this case, the timing of the guide wheel contacting the guide rail (the contact period) and the timing of the right and left front wheels moving from a straight section into a curved section (the curve entry period) are within a predetermined range. On the other hand, when the guide rail is not positioned within an appropriate range, the timing of the contact period and the curve entry period will be outside the predetermined range. According to this configuration, considering the relationship between the curve entry period and the contact period, it is possible to determine whether the guide rail is positioned within an appropriate range based on the timing of the curve entry period and the contact period. In this way, according to this configuration, the position of the guide rail can be checked based on the behavior of the trolley to see if it is within an appropriate range.

[0075] Ideally, the aforementioned guide rail is positioned on the upper side relative to the pair of aforementioned travel rails. During the aforementioned rail inspection process, if the aforementioned contact period precedes the aforementioned curve entry period and exceeds a predetermined judgment range, it is determined that the setting position of the aforementioned guide rail is deviated from the aforementioned appropriate range towards the side of the aforementioned contact wheel in the aforementioned width direction.

[0076] When the guide rail is positioned above a pair of travel rails, during the trolley's movement in a curve, to maintain the trolley's posture such that the contact wheel contacts the corresponding travel rail and the separating wheel separates from the corresponding travel rail, the guide wheel contacts the guide rail from the side of the contact wheel in the width direction. Therefore, when the guide rail's position is offset towards the contact wheel side in the width direction relative to an appropriate range, the contact time becomes earlier than the curve entry time. Based on this configuration, the relationship between the curve entry time and the contact time can be considered to appropriately determine whether the guide rail's position is offset towards the contact wheel side in the width direction relative to an appropriate range.

[0077] Furthermore, ideally, the aforementioned guide rail is positioned on the upper side relative to the pair of aforementioned travel rails. During the aforementioned rail inspection process, if the difference between the aforementioned contact period and the aforementioned curve entry period is within a predetermined judgment range, it is determined that the setting position of the aforementioned guide rail is within the aforementioned appropriate range, or that the setting position of the aforementioned guide rail is deviated from the aforementioned appropriate range towards the side of the aforementioned split wheel in the aforementioned width direction.

[0078] As mentioned above, when the guide rail is positioned above a pair of travel rails, the guide wheel contacts the guide rail from the side of the contact wheel in the width direction when the trolley travels in a curve section. Therefore, when the guide rail is positioned relative to an appropriate range towards the side of the separating wheel in the width direction, the contact period becomes later than the curve entry period. However, when the curve entry period is determined based on the change in trolley behavior caused by the guide rail's guiding effect on the guide wheel, the curve entry period determined by the curve entry period determination process, like the contact period, becomes later as the guide rail is positioned towards the side of the separating wheel in the width direction. As a result, even when the guide rail is positioned relative to an appropriate range towards the side of the separating wheel in the width direction, the curve entry period can still be determined to be the same as the contact period, just as when the guide rail is positioned within an appropriate range. According to this configuration, when determining the curve entry time based on the change in trolley behavior caused by the guiding effect of the guide rail on the guide wheel, as described above, it can be appropriately determined that the guide rail's installation position is within an appropriate range, or that the guide rail's installation position deviates from the appropriate range towards the side of the separating wheel in the width direction. In other words, it can be appropriately determined that the guide rail's installation position does not deviate from the appropriate range towards the side of the contact wheel in the width direction.

[0079] Furthermore, ideally, it also includes a measuring unit that measures the rotational speed of the right front wheel and the left front wheel or a speed proportional to that rotational speed, and a determination unit that determines the period of vibration of the speed detected by the measuring unit as the contact period.

[0080] According to this configuration, the contact period can be appropriately determined based on the vibration of the rotational speeds of the right and left front wheels caused by the impact of the guide wheels contacting the guide rail. Furthermore, when the trolley is a self-propelled trolley, a measuring unit is usually installed to control its movement. This measuring unit measures the rotational speeds of the right and left front wheels, or speeds proportional to those rotational speeds. In such cases, according to this configuration, the contact period can be determined using the trolley's existing measuring unit without the need for additional sensors.

[0081] Furthermore, ideally, it also includes a measuring unit that measures the rotational speed of the right front wheel and the left front wheel, or a speed proportional to that rotational speed, as well as the rotational speed of the right rear wheel and the left rear wheel, or a speed proportional to that rotational speed. The determination unit determines the period when the speed difference between the front and rear wheels has reached or exceeded a predetermined value as the period of entering the curve. The speed difference between the front and rear wheels is based on the difference between the rotational speeds of the right front wheel and the left front wheel and the right rear wheel and the left rear wheel, as determined by the measurement results of the measuring unit.

[0082] As the trolley enters the curve from a straight section, the arrangement of the right front wheel, left front wheel, right rear wheel, and left rear wheel in the straight section changes to a configuration where the right front wheel and left front wheel are in the curve while the right rear wheel and left rear wheel are in the straight section. With this change in configuration, the speed difference between the front and rear wheels changes from zero or near zero to a value determined by the curvature of the curve. This speed difference is the difference between the rotational speeds of the right front and left front wheels and the right rear and left rear wheels. Based on this configuration, by detecting this change in the speed difference between the front and rear wheels before and after the right front and left front wheels enter the curve, the timing of the curve entry can be appropriately determined.

[0083] In the above configuration, ideally, the determination unit uses the difference between the rotational speeds of the right front wheel and the left front wheel and the rotational speeds of the right rear wheel and the left rear wheel after removing the high-frequency components as the difference between the front and rear wheel speeds to perform the aforementioned cornering entry time determination process.

[0084] According to this configuration, since the difference in front and rear wheel speeds used to determine the cornering entry time can be set as the value after removing minor vibration components from the difference in rotational speeds of the right front and left front wheels and the right rear and left rear wheels, the cornering entry time can be determined more appropriately.

[0085] Furthermore, ideally, the aforementioned trolley is a transport vehicle that holds and moves items, and the aforementioned determination unit performs the aforementioned contact period determination process, the aforementioned curve entry period determination process, and the aforementioned track inspection process during the movement of the aforementioned transport vehicle.

[0086] According to this configuration, a transport cart for moving items can be used as a trolley for this inspection without using a dedicated trolley for checking whether the guide rail is positioned within an appropriate range. Furthermore, since this inspection can be performed while the transport cart is moving, the inspection can be carried out simultaneously with the transport cart moving the items.

[0087] The track inspection device disclosed herein only needs to perform at least one of the aforementioned effects.

[0088] 1: Track inspection device 2: Items 10: trolley 11: First Walking Section 12: Second Walking Section 13: Ontology part 20A: Contact wheel 20B: Separate wheel 21: Left rear wheel 22: Right rear wheel 23: Front left wheel 24: Right front wheel 40: Guide wheel 41: Rear idler wheel 42: Front idler wheel 51: Left rear auxiliary wheel 52: Right rear auxiliary wheel 53: Front left auxiliary wheel 54: Right front auxiliary wheel 60: Control Department 61: Judgment Department 62: Contact Period Determination Department 63: Corner Entry Period Judgment Section 64: Track Inspection Department 70: Walking Path 71: Linear Interval 72: Curve Section 80: Walking Track 81: Left track 82: Right Track 83: Guide Track 83A: Conical surface 83B: Guiding Surface 100: Goods conveying equipment A1: First Axis A2: Second Axis B: Boundary B1: First Boundary B2: Second Boundary G1: First output signal G2: Second output signal H: Vertical direction of the vehicle body L: Front and rear directions of the vehicle body M1: First Drive Unit M2: Second Drive Unit M3: Third Drive Unit M4: 4th Drive Unit P0: Position 0 P1: First Posture P2: Second posture P3: Third Posture P4: Fourth Posture P5: Fifth Posture P6: Sixth Posture P7: The 7th Posture S: Measurement Department S1: First Measurement Section S2: Second Measurement Section T1: Contact Period T2: Corner Entry Period V1: First speed V2: Second speed VD: Speed ​​difference between front and rear wheels VF: Front wheel rotation speed VR: Rear wheel rotation speed X: Direction of movement X1: Front side X2: Rear side Y: Width direction Z: Up / Down direction Z1: Lower side Z2: Upper side

Claims

1. A track inspection device comprising a trolley that travels along a pair of travel tracks and a guide track in a travel direction, the track inspection device having the following characteristics: a width direction orthogonal to the travel direction is defined in a vertical view; the pair of travel tracks are arranged parallel to each other in the width direction and include a straight section where the travel direction is straight and a curved section where the travel direction is curved; the guide track is provided at least in the curved section and is arranged parallel to at least one of the pair of travel tracks at different positions in the vertical direction relative to the pair of travel tracks; the trolley comprises: a right front wheel and a left front wheel arranged in the width direction; a right rear wheel and a left rear wheel arranged further rearward in the travel direction than the right front wheel and the left front wheel, and arranged in the width direction; and a guide wheel, the right front wheel and the right rear wheel being configured to roll on one of the pair of travel tracks, namely the right track. The aforementioned left front wheel and left rear wheel are configured to roll on the left track, the other of the aforementioned travel tracks. The aforementioned guide wheel is configured to contact the aforementioned guide track from one side in the aforementioned width direction and roll. When the aforementioned trolley travels in the aforementioned straight section, the aforementioned right front wheel and right rear wheel contact the aforementioned right track and roll, and the aforementioned left front wheel and left rear wheel contact the aforementioned left track and roll. The aforementioned guide wheel is separated from the aforementioned guide track. When the aforementioned trolley travels in the aforementioned curved section, one of the combination of the aforementioned right front wheel and right rear wheel and the combination of the aforementioned left front wheel and left rear wheel becomes a contact wheel that contacts the corresponding travel track and rolls. The other of the combination of the aforementioned right front wheel and right rear wheel and the combination of the aforementioned left front wheel and left rear wheel becomes a separating wheel that is separated from the corresponding travel track. Furthermore, the aforementioned guide wheel contacts the aforementioned guide track and rolls. The aforementioned track inspection device further includes a determination unit, which performs contact period determination processing, curve entry period determination processing, and track inspection processing. The aforementioned contact period determination process is the process of determining the period when the aforementioned guide wheel contacts the aforementioned guide rail, i.e., the contact period. The aforementioned curve entry period determination process is the process of determining the curve entry period. The aforementioned curve entry period is the period when the aforementioned right front wheel and the aforementioned left front wheel enter the aforementioned curve section from the aforementioned straight section. The aforementioned rail inspection process is the process of determining whether the setting position of the aforementioned guide rail is within an appropriate range based on the relationship between the aforementioned curve entry period and the aforementioned contact period.

2. The track inspection device of claim 1, wherein the aforementioned guide rail is disposed on the upper side relative to the pair of aforementioned travel rails, and in the aforementioned track inspection process, when the aforementioned contact period is earlier than the aforementioned curve entry period and exceeds a predetermined judgment range, it is determined that the setting position of the aforementioned guide rail is deviated from the side of the aforementioned contact wheel in the aforementioned width direction relative to the aforementioned appropriate range.

3. The track inspection device of claim 1 or 2, wherein the aforementioned guide rail is disposed on the upper side relative to the pair of aforementioned travel rails, and in the aforementioned track inspection process, when the time difference between the aforementioned contact period and the aforementioned curve entry period is within a predetermined judgment range, it is determined that the setting position of the aforementioned guide rail is within the aforementioned appropriate range, or that the setting position of the aforementioned guide rail is deviated from the aforementioned appropriate range toward the side of the aforementioned split wheel in the aforementioned width direction.

4. The track inspection device of claim 1 or 2 further includes a measuring unit that measures the rotational speed of the right front wheel and the left front wheel or a speed proportional to the rotational speed, and the determining unit that determines the period of vibration of the speed detected by the measuring unit as the contact period.

5. The track inspection device as claimed in claim 1 or 2 further includes a measuring unit that measures the rotational speed of the right front wheel and the left front wheel or a speed proportional to the rotational speed, as well as the rotational speed of the right rear wheel and the left rear wheel or a speed proportional to the rotational speed. The determining unit determines the period when the speed difference between the front and rear wheels has reached or exceeded a predetermined value as the period of entering the curve. The speed difference between the front and rear wheels is based on the difference between the rotational speeds of the right front wheel and the left front wheel and the rotational speeds of the right rear wheel and the left rear wheel, as determined by the detection results of the measuring unit.

6. The track inspection device of claim 5, wherein the aforementioned determination unit uses the value obtained by removing high-frequency components from the difference between the rotational speeds of the aforementioned right front wheel and the aforementioned left front wheel and the rotational speeds of the aforementioned right rear wheel and the aforementioned left rear wheel as the aforementioned front and rear wheel speed difference, and performs the aforementioned curve entry time determination process.

7. The track inspection device as claimed in claim 1 or 2, wherein the aforementioned trolley is a transport vehicle that holds and transports items, and the aforementioned determination unit performs the aforementioned contact period determination process, the aforementioned curve entry period determination process, and the aforementioned track inspection process during the movement of the aforementioned transport vehicle.

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